Latest ultra-low-power PMIC enables high sensitivity optical measurements

The ultra-low-power MAX20345 from Maxim Integrated Products integrates a lithium charger and debuts a unique architecture that optimises the sensitivity of optical measurements for wearable health and fitness applications. The device offers a first-of-its-kind buck-boost regulator based on an innovative architecture that’s optimised for highly accurate heart-rate, blood-oxygen and other optical measurements. The regulator produces the desired low-quiescent-current performance with no drawback that can degrade SNR and, consequently, can improve performance by up to 7dB (depending on measurement conditions). The device is also the newest in a line of ultra-low-power PMICs for small wearables and IoT devices that further raise efficiency without sacrificing battery runtime. To satisfy these requirements, the device combines a lithium-ion battery charger; six voltage regulators, each with the ultra-low quiescent current; three nanoPower bucks (900nA typical) and three LDO regulators with ultra-low quiescent current (as low as 550nA typical). Two load switches enable disconnecting of system peripherals to diminish battery drain. Both the buck-boost and the bucks support DVS, offering extra power-saving opportunities when lower voltages can be deployed under positive conditions. The device is offered in a 56-bump, 0.4mm pitch, 3.37mm x 3.05mm wafer-level package.